Photonic front-end for millimeter wave applications

Abstract

We propose theoretically and demonstrate experimentally both a direct (quadratic) and a coherent millimeter wave photonic receivers operating at 35 GHz carrier frequency. These devices are made based on lithium niobate or lithium tantalite or quartz optical whispering gallery mode resonators coupled to a millimeter wave signal with a strip line. The quadratic receiver has sensitivity exceeding -70 dBm in a 3 MHz frequency band. It also has more than 40 dB of dynamic range. The coherent receiver can have a dynamic range in excess of 100 dB in a 5 MHz band, as well as a much higher sensitivity. The coherent operation of the receiver is achieved using a millimeter wave local oscillator fed into the strip line resonator along with the millimeter wave signal. We also discuss possible photonic methods for the generation of spectrally pure local oscillator signals suitable for the application in the coherent receiver.